地埋滴灌点源入渗土壤水分运动规律实验研究

通过室内砂土中进行地埋滴灌的实验,对地埋滴灌在砂土中的适应性进行初步研究,为田间试验布置提供依据。通过分析湿润锋的推移速率、特征点的土壤含水率变化规律,发现湿润锋推移速率先是径向大于垂向,随着灌水时间和灌水量增加,水平方向和垂向的湿润锋和含水率趋于平衡。根据对比滴灌带埋深15和20 cm特征点的含水率变化情况,得出埋深15 cm节水效果更好,更利于作物生长。实验还得出湿润比能作为滴灌灌水参数的指标,由于作物种植的间距和作物根系深度之比基本小于1.0,因此在田间实际灌溉中湿润比应控制在1.0左右。

A Study on Soil Water Movement Law of Point Sourec Infiltratio nunder Buried Drip Irrigation

indoor sand to provide basis for the field experiment layout.Through the analysis of the transition velocity of wet front and the soil water con-tent variation law of characteristic points, it is found that the transition velocity in radial direction is greater than that in vertical direction;with the increase of irrigation time and irrigation amount, the wetting front and moisture content in the horizontal and vertical direction get balance.The contrast of the moisture content of the characteristic points of 15 cm and 20 cm drip irrigation belt buried depth indicates that the water-saving effect of 15cm drip irrigation belt buried depth is better and more beneficial for the crop growth.The experiment results also show that wet ratio can be used as an irrigation indicator parameter, and its value should be controlled around 1.0 since the ratio of crop spacing to crop root depth is usually less than 1.0.